Comment 28 for bug 1624320

Anders, are you still seeing this issue with currently-supported versions of Ubuntu? I have argued elsewhere that the correct thing to do for 18.04 is to forcibly remove resolvconf on upgrades, switching /etc/resolv.conf to exclusively point to /run/systemd/resolve/stub-resolv.conf. In the common case, however, this should not make a difference. What other sources of DNS settings do you have that are feeding directly to resolvconf instead of resolved in 16.10 and later?